Aeronautical device



J. P. BUCKLEY Re. 21,838 AERONAUTICAL bEvIcE Original Filed July 10, 1929 3 Sheet's-Sheet 2 June 24, 1941.

A llomey June 24, 1941. J. P. BUCKLEY Ra 21,838

AERONAUTICAL DEVICE Original Filed July 10, 1929 s sheets-sheet :s

FIG. 10.

A 0-H TRANSM FI'TLR. 2e

I port an aviator Reissue d June 24, 1941 UNITED STATES PATENT OFFICE John P. Buckley,

Washington, D. (3., assignor of one-half to Ben J. Chromy, Washington, D. 0.

Original No. 2,081,134, dated No. 377,156, July 10, 1929. issue March 29, 1939, Serial No.

25 Claims.

This invention relates to aeronautical devices of the fog signaling type generally. More particularly this invention relates to apparatus for automatically determining fog and cloud bank heights and transmitting signals in accordance therewith.

An object of this invention is to provide automatic ,means ior broadcasting a signal when the ceiling height of log or visibility becomes too' low for an aeroplane to safely land.

Another object of this invention is to provide an apparatus for automatically determining the ceiling height at a predetermined location for indicatingthe upper surface of a fog bank existing at that location.

In accordance with this invention 1 provide a system which may be used advantageously on high precipices, termine when the upper surface of the fog bank has settled just above the mountain peak or below the peak, By using this system when flying through a dense fog towards a mountain or aircan readily determine whether or not a high ceiling prevails thereon or thereover.

With these and other objects in view the invention consists of the novel construction, ar-

rangement and formation of parts as will be hereinafter more specifically described and illustrated in the following specification, claims and drawings. Referring to the drawings briefly,

Fig. 1 is a view illustrating the use of two intersecting light beams for determining the height of clouds or a fog bank; s

Fig. 2 is an'enlarged elevation of search light employed in accordance with this invention; Fig. 3 is a rear view of a search light employed in accordance with this invention; i

Fig. 4 is of a photo-cell casing showing an automatic shutter arrangement;

Fig. 5 is a schematic diagram of a light sensitl-ve cell and associated control circuits embodied in this invention; i

Figs. 6 and 7 are, respectively, a front elevation and side elevation of a modified form of the search light apparatus employed in accordance withthls invention;

- Figs. 8 and 9 are detail views of the circuit controlling apparatus associated with the search lightofFlg. 6; g I

Fig. 10 shows a schematic diagram of connec May 25, 1937, Serial Application for resuch as, mountain tops, to de- Fig. 11 is another modified tion;

Fig. 12-15 Fig. 11;

. Fig. 13 shows the apparatus of this invention positioned on a mountain peak or precipice.

The numeral l designates a landi field for form of the invena top view of the searchlights oI aeroplanes, dirigible's and similar aircraft on which are positioned search light members 3, spaced apart and electrically connected by cable 2. The'lamp 4, of each of the search light members, is positioned in thecasei which supports the lens 6 and is pivotally supported by the stud I and the standard 8.

The clamping bolt 3 is provided with a pointer III, which traverses the scale II and indicates the angle of the search light beam. The photocell l2 is housed in casing l3, the upper portion of which is'provided with a tubular member -l|, through which light passes to the cell when the shutter I5 is opened. A pivoted armature V I6 and solenoid II are provided to control the shutter l5. Lens I8 is positioned in the member I4 for focusing light reflected from the spot l5, appearing on the underfsurface of the fog bank 20. The spot I! is formed on the underside of the cloudor fog bank 20 by the beams 21 and22 transmitted from the search lights 3. The light sensitive cell l2, positioned in the housing I3, is located below the spot I! as illustrated in Fig. l. A bracket arm 23 is supported by the member M for pivotally supporting the shutter tlons between the commutator disc, code wheel and solenoid, associated with the searchlight ap paratus of Fig. 6;

at point 24.

The loop antenna 25 is electrically connected with the radio transmitter 26, and while I have shown a loop antenna in thisparticular instance for radiating the electrical ene any other style of antenna, as illustrated in Fig. 5, may be used effectively as well.

Referring to Fig. 5, the circuit control apparatus 21', including the shaft 28, the gear 29 and worm 30 and the circuit interrupting discs 31,

H and 42 are p ovided to control the. op ration of the signal transmitter -26 after the circuit between the contacts 50" and the relay armature 59 are closed. Adjacent to the gear 25 and fixedto the shalt is a cam 32, having a notch ll for engagement with pin 34. The pin 34 of switch arm 35 engages the periphery of the cam and serves to prevent the operator from opening'the motor circuit 35, until a predetermined point of the cam is reached with respect to the other circuits controlled by the shaft movement. In this way, as is illustrated by the drawings, the circuit or the motor 3| may be lnterruptedonly when being of any conventional design, may head the circuits controlled by the discs 31 and 42 'are also interrupted.

The insulation disc 31 carries metallic segments 38 and 39, which are electrically connected by wire 48. The. metallic key disc 42 fixed on the shaft 28, has two metallic segments 43 and 44 whichare joined together by link wire 45. The brushes 46, 41,48, 49, and 58, electrically contact with the discs associated therewith and the brush forms a contact with the shaft to complete the circuit through [the metal code disc 4|, the brushes 48, 49, and 58 and the segments 43 and 44 of the disc 42.

Thebrushes 46 and 41 are associated with the disc-31 to contact segments 38 and 39 and periodically interrupt the circuit 52' of the solenoid l1 which is connected Ito these brushes and the current supply 56 .by the wiresv 53; 54, and 55.

complislred .by imparting a reciprocating motion The brush 48 contacts with the code letter disc 4| and serves to break the current fromthe transmitter 26 .into signal letters. The keying disc 4| is connected through the'shaft'28 and its associated brush 5| to the cathode circuit of the transmitter 26. Brushes 48 and 49 are connected together, as illustrated. 'Brushes 49 and 58 cooperate with the segments 43-and 44 of the disc 42 to compl-etethekeying circuit of the transmitter 26 onlywhile the brush 48 is on the coded portion of the disc 4|; Connections 58, 5|

and 62 are provided between the relay armature 59, the radio transmitter 26, the relay contact 68" and the brushes 58 and 5|. These connections cooperate with the keying disc 4| and the segments 43 and 44 of disc 42, which are connected together by the connection 45, to control the keying of the radio transmitter 26. u

The circuit 63 'of the search lighit3 is'automatically controlled by the metallic blade. 65 of the shutter arm 64, which is of suflicient size to bridge over contacts and 61 when drawn downward-bythe solenoid H. The lamps 3 are connected in series by the connection 69 Connection 68 is provided between one of the lamps 3 l and con-tact 66 and connection 18 is provided between the otherlamp 3 and the-current supply 1| which in turn is connected by wire .12 to the contact 61.

In-operation the switch is'pulled outward and thecircuit 36 of the motor 3| is closed. The

motor thereupon rotates the shaft 28 together with the solenoid-circuilt-interrupting disk 31, the transmitter coding disc '4 [and the interrupting disc 42. The shutter l5, which controls the light to the sensitive cell |2,- is thus periodically raised and lowered through the periodic energization of the solenoid I1 and the 'lamps 3 are also periodically energized through the operation of the switch blade-65. If a'refiecting medium exists above the lamps 3 iltwill reflect light to the light sensitive cell I2, which is coupled to toeach of the search light members 13, which correspond to the search lights 3 of Fig; l.

The motor 18' rotates the gear 19, shaft 18 and crank disc 16'. The crank disc with the cooperation of the pin 11 and the arm 15 imparts an oscillatingmotion to the arm 14 and the lamp 13 which issupported by the member 83, as il-' lustrated in Figs. 6 and 7. Fixed to the shaft also is the driving member 88 having. an arm to engage the pin 8|, of: code signaling wheel 82,

upon the periphery of which are placed the vari- C ous dots and' dashes, identifying the changing angles of :thelight beams. Secured to the codewheel 82 is shaft 83,'which in turn supports the starwheel 84 in fixed relation thereto, and com-.

mutator 85 of insulating material. The star wheel 84 engage a. roller 86 at the free end or alettching arm which is pressed down by a spring 81. The commutator disc 85 is provided with contacts 88, all of which are connected with the ring wire 89, which is electrically grounded to the shaft as at point- 98. commutator 85 is insulated from the frame by insulation block 92. The frame 93 supports the solenoid 94, having an armature 95 and roller 95, backwardly controlled by spring 96, and forwardly controlledby the solenoid when energized.

The embodiment of this invention illustrated .in Figs. 6, '1, 8, 9, and 10 operates as follows: The motor 18' which causes the lamp 13 to oscillate up,

and down also rotates ,the commutator 85, the star wheel 84 and the code wheel 82, through the operation of-the pin 8| and the arm of -member 88. When the brushf9| which is associated with the commutator, asillustrated lnFigs. 6, 8;

and 10, contacts with one of the segments 88. of the commutator 85 the circuit through the solenoid 94 is completed and the contactor 95"is' caused to traverse the cod wheel 82. This code wheel is connected through the shaft 83 and=the solenoid contactor 95' to the keying circuit of the I transmitter 26 (Fig. 5). In this way'this circuit arrangement of Fig. 10 may be used in place of the code wheel 4| of Figl 5 by connecitingthe the input of the amplifier 63 .by resistance units R2 and R13 and capacity C2. The amplifier 63 energizes the-relay 68 and causes this relay to close the circuit between the armature59 and.

the contact 68" when the cell I2 is energized by the. proper radiant energy. The keyin'g'disc 4| and circuit interrupting disc 42, being rotated by the shaft 28, cause the transmitter 26 to transmit signals characteristic of low visibility conditions over the airport or air route, in accordance with a certain predetermined code.

It is, of course, obvious that the amplifier 26 justed so that the relay 68 will either close or open the circuit between armature 59 and'conleads 58 and 62 to the armature and the shaft 83' (Fig. 10) respectively, instea'd'of the brushes' 58 'and-5l-of Fig. 5.f This code wheel 82, armature 95 and the electrical circuit associated therewith function to key or modulate the transmitter 26 in accordance with-different code characters which correspond to different angular positions of the light beam with respect to a base lineor plane. It is of course obvious that the distance between the cell l2 and the light spot l9 (Fig. 1) may be readily determined when the distance between the cell 2 and. the light source 4 is known and the angle of the beam 22 with respect to the plane I is also known.

The winding of the-relay 68, which controls the circuit of the lead 62 to the transmitter 26, is connected to the output circuit of the amplifier 63. The input circuit of the amplifier 6315 con-.' nectedto the photo-electric -cel1 l2 in the same either I The brush 9| ofthe patform. I which source 56 is employed to energize the solenoid 04 of the contacting mechanism 96, as illustrated.

The star wheel 84 of Figs. 6 and 8 operates to make the angular movement of the code wheel 82 non-uniform. The roller 06 supported upon the periphery of the star wheel 84, is caused to bear down upon this latter Wheel, by the spring 01. Inthis way the star wheel is rotated uniformly as this roller is caused to mount the crests formed on the periphery'of this wheel; and a slight and rapid forward movement is imported to this wheel, through'th action of the spring 81 and the weight of the roller apparatus, as this roller sinks into the valleys of the star wheel.

In operation the motor also partly drives the code wheel by the arm and'pin movement, by

one-half tooth of the star wheel, at which point the spring, bearing on the arm carrying the roller, pushes the star wheel forward clear of the arm piece 80 and settles quietly forward again to contact with the pin for another one-half tooth movement. In this way alternating rest steps are imparted to the star wheel 84, likewise to the commutator disc 85, at which time electrical contact is made with the brush 9|, and the solenoid is energized and pushes the roller 86, over the dot and dashes, thus automatically broadcasting the danger signal, as in the case of the fixed light beams.

Figs. 11 and 12 illustrate another modified form of the invention in which a single lightspot effect 99 is brought about by employing two or more light beams from search lights 98. The angle of intersection may be regulated to form the central lightspot at any height.

A pedestal 91. is employed for supporting two or more light reflecting members 98 on the top I00 thereof to project a plurality of light beams into a given direction or directions and form the .lightspot 99 at a predetermined height. Located in the center of the table top I00, and extending downward is the channelv I0 I the bottom of which is enlarged and houses the photo-cell I02. The channel and photo-cell are placed directly in the center and in alignment with the lightspot, the light waves of which are free to pass on through the channel to the photo-cell.

The electrical connections employed in the embodiment of this invention shown in Figs. 11 and 12 are the same as in Fig. 5, employing the photo-cell and transmitter circuits together with the switch controls except that the contact 60'? is positioned on the opposite side of the armature 50. of relay 00. V

Another embodiment of this invention is shown in Fig. 13, wherin the signaling apparatus employedfor detecting the appearance of fo is positioned on a mountain peak or precipice. Signals are broadcast from the apparatus thus located to be intercepted by aircrafo pilots navig'ating in regions surrounding the mountains.

A' pair of search lights 90 are mounted on a is pivoted on the upright member 8, standing on the prominence I01, such as, a mountain peak or precipice. Beams I06 are projected upwardly from the searchlights tothe clouds and form the light-spot 99 from which lightis reflected to the light sensitive element I 02 which is positioned in the casing I IIII.

until the arm is moved A pointer I0 is attachedto the member I00 and indicating the angl and elevation of the cloud bank with respect to some predetermined altitude. The beams I06 may be tilted downward as indicated by the line I01 and may be used to indicat the presence of clouds I08.

The cloud indications determined-by this arrangement are transmitted in the manner described to aircraft I09 or to distant observation points as desired. Y

While I have described my invention in certain of its preferred embodiments in detailit is, of course, understood that I do not desire to limit it to those exact details except in so far as they may be defined by the appended claims.

-I claim:

1. Signaling apparatus comprising lamps pivotally mounted for, movement in a vertical plane whereby light beams may be projected upwardly to intersect at different altitudes and form a light spot upon the lower surface of a cloud bank at different altitudes. a light sensitive cell positioned beneath said light spot for energization by light transmitted from said light spot, signaling apparatus connected to be controlled through the operation of said light sensitive cell and means for automatically broadcasting a different signalfor each cloud bank altitude from said signaling apparatus when said cell is energized.

2. Signaling apparatus comprising lamps pivotally mounted for movement in a vertical plane whereby light beams may be'projected upwardly to intersect at predetermined altitudes and form a light spot upon a cloud bank or similar obstruction, alight sensitive cell mounted between said lamps beneath said light spot for energization by light transmitted from said spot, means for transmitting an indication determined by the altitude of said light spot to a remote point and means having a circuit connected to said light sensitive cell for controlling the energization of ,said first mentioned means in accordance with the energization of said light sensitive cell.

3. Signaling apparatus comprising means for projecting light beams upwardly at. an incline to form a light spot upon a cloud bank at predeter- 4. Signaling apparatus comprising a searchlight pivotally mounted to project a beam of light at different angles upward to a cloud bank, a code wheel mounted adjacent to said search-light, a contacting member. associated with said code wheel for. contacting different code characters on said wheel as said wheel is moved through predetermined angles, means for oscillating said search-light and saidcode'wheel through predetermined angles substantially simultaneously, a light sensitive element positioned to receive light reflected from said cloud bank, means for transmitting a radio 'signal in accordance with the energization of said light sensitive element and means for modulating said radio signal in accordance with the code characters contacted on said code wheel when said radio transmitter is ward to form a light spot upon a cloud bank, a 5

light sensitive cell positioned to be energized by light reflected from the light spot formed on' the cloud bank, signal transmitting apparatus and means connected to said light sensitive cell and said transmitting apparatus for controlling the operation of said signal transmitting appa ratus in accordance with the energization or deenergization of said light sensitive cell.

6. Signaling apparatus comprising means for projecting light beams upwardly to interact l5 and form a light spot upon a cloud bank at predetermined altitudes, means for determiningthe height of said light spot cooperating with said means, a light sensitive cell mounted to receive light transmitted from said light spot, a signal transmitter, a relay, means connected to the con tacts of said relay to control said transmitter,

I a 'means connected to said light sensitive cell I01 controlling said relay and transmitter in accord ance with the energization of said cell and means connected to said first mentioned means and said signal transmitter for causing said transmitter to transmit different signals for different light spot altitudes.

-7. In aeronautical signaling apparatus the combination of an oscillating'light beam emitting device, means for directing the light beam in predetermined directions for forminga light spot on cloud banks existing at different positions, means -fcr translating light energy received from said 3 light spot into electrical energy, radio signaling apparatus, means connected to said light energy translating means for controlling the operation of said radio signaling apparatus and for effecting the transmission of different signalsfrom 40 said radio signaling apparatus for difierent cloud bank positions.

8. In aeronautical signaling apparatus the combination of 'a pair of oscillating light beam emitting devices, means for oscillating said devices in synchronisrn and for directing the light beams in predetermined directions for forming a light spot on'cloud banks at different positions, means for translating light energy received from Said ht spot into electrical energy, radio signaling apparatus, means connected to said-light energy translating means for controlling the operation-of said radio signaling apparatus and for eflecting the transmission of differentv signals from said radio signaling apparatus for different cloud bank altitudes.

9. Signaling apparatus including means for.

projecting lightbeams upwardly at an incline to form a light spot upon a cloud bank, a light sensitive cell, means cooperating with said first mentioned means for synchronously moving said light beams to form said'light spot on cloud banks at{ different altitudes, means cooperating with said light sensitive cell, said 'first and said second means for selecting a signal characterized by the altitude of the cloud bank on which said light spot is formed and for transmitting said signal to. a remote point:--

10. Signaling apparatus comprising means for.

projecting a light beam upward. at ,difierent H of radiant energy pivotallymounted to swingthrough a predetermined angle with respect to light energy into electrical energy, signal'transmitting means, connections between said light responsive means and said signal transmitting means, keying meansconnected to said signal transmitting means, saidkeying means being controlled by said first means for effecting the a radio transmitting system, a lightsensitive cell, means for connecting said cell to the input circuit of said ra'dio transmitting system, a light source pivotally mounted-to project a sweeping beam of light in search of bodies of light obstructing material, said light sensitive cell being positioned to receive light from said light obstructing material only during a certain predetermined portion of said sweeping movement of said beam, means cooperating with said light source for'determining the position of said light obstructing material when said cell is-energized andmeans connected to said radio transmitting systemior transmitting a predetermined signal for each determined position.

l2. Signaling apparatus comprising a pair of searchlights pivotally mounted to project beams of light upward to a cloud bank, means for moving said searchlights with respect to their pivots until the beams of said searchlights intersect and form a light spoton a cloud bank, a light sensitive element for translating light energy into electrical energy positioned to receivelightreflected from said light spot, a radio transmitter connected to be controlled in accordance with the energization of said light sensitive element and means connected to said transmitter for effecting the transmission of different characteristics from said radio transmitter for different .cloud bank light spot altitudes.

l3. Signaling apparatus comprising means for projecting a beam of light to a cloud bank, a

- light sensitive cell positioned to be energized by light reflected from said cloud bank, means co-' operating with'said first means and said cell for determining the height of said cloud bank when said cell is energized and means for transmitting beams converge for the operation thereof, and

signalproducing means mechanically connected to said first mentioned means and connections for connecting said signal producing means to said radiant energy receiving meansfor energizing and actuating said signal producing means when said receiving means is energized so that said signal producing means produces signals characteristic of the distance between said radiant energy obstructing object and said receiving means each time said radiant energy receiving means is energized by reflected radiant energy from-said beams converging on a refleeting object. i a

15. Signaling apparatus, comprising: a source a reference line and project a sweeping beam of radiant energy in search of objects at least partially obstructing the passage of such radiant enon the angular position of said sounce of ergy, a member bearing predetermined legends corresponding to predetermined angular positions of said pivotally mounted source of radiant energy, said member being mechanically coupled with' said pivotally mounted source of radiant energy, a cellsensitive to said radiant energy, said cell being fixedly positioned to receive radiant energy reflected fromsaid obstructing objects, and means connected to be controlled by said cell when said cell is energized for producing electrical signals corresponding to said legends of said member, electrical signals being produced depending upradiant energy when said cell is energized.

16. Signaling apparatus, comprising: a source of radiant energy, pivotal mounting for said source, means for oscillating said source through predetermined angles to project asweeping beam of radiant energy in search of objects tending to obstruct the passage of such radiant energy, a member having a plurality of angle identifying legends thereon corresponding to different angular positions of. said pivotally mounted source of radiant energy with respect to' a reference line, means for connecting said member to said pivotal mounting, a cell sensitive to said radiant energy, said cell being positioned to receive radiant energy reflected toward said cell along -a predetermined line with respect to the ducing electrical signals corresponding to .the angle at which said pivotally mountedsource of radiantenergy is disposed with respect to said reference line when said cell is energized.

difierent ones of said aforesaid reference line, means responsive to the energization of said cell for pro- 1'7. Signaling apparatus, comprising: a source of radiant energy pivotally mounted to project a beam of radiant'energy in search of objects adapted to reflect at least some of the radiant energy, receiving means responsive to radiant energy reflected from any such objects; a member carrying a plurality of angle identifying legends, means for moving said member in accordance'with the movement of said pivotally mounted source of radiant energy, and electrically energized means responsive to said receiv-.

ing means for producing signals corresponding to the angle identifying legend characterizing the angle at which said pivotally mounted source "'of radiant energy is disposed when said receiving means is energized. v

18. Signaling apparatus. comprising: a source of radiant, energy pivotally mounted to project 'a beam of radiant energy insearch of objects adapted to reflect at least some of the radiant energy, receiving means responsive to radiant e' rg reflected from any such objects. a member c arrying a plurality of angle identifying legen which; said pivotally mounted source of radiant energt is adapted to be disposed with respect to a reference line, means pivotally mounted source of radiant energy, and means responsive to saidlreceiving means for producing electrical impulses corresponding to for identifying a plurality of angles at for moving said member in accordance with the movement of said adapted to reflect large percentages of such radiant energy, radiant energy sensitive receiving means for receiving radiant energy reflected from said object, and means responsive to said receiving means for producing different electrical impulses for each different angle at which said first mentioned means is disposed when the radiant energy reflected from said object energizes said receiving means.

20. Signaling apparatus, comprising: means for-oscillating a beam of radiant energy through a predetermined angle with respect to a reference line across surfaces of an object normally adapted to reflect large percentages of such radiant energy, a single fixed radiant energy sen,- sitive receiving means positioned to be energized by the radiant energy reflected from said object, an amplifier connected to said receiving means, and means connected to said amplifier for producing different electrical impulses for each different angle at which said first mentioned means is disposed when the radiant energy reflected from said object energizes said receivject, and means responsive to said receivingmeans for producing different electrical impulses for different distances between said radiant energy reflecting object and said receiving means.

22,- Signaling apparatus, !compri'sing: a source of radiant energy pivotally mounted to project a beam of radiantenergy in search of'objects adapted to reflect at least some of the radiant energy, receiving means responsive to radiant energy reflected from any such objects, a member carrying a plurality of angle identifying legends of conducting material for identifying a plurality 'of angles at which said" pivotally mounted source of-radiant energy isadapted to be disposed with respect to a reference line, means for moving said member in accordance with the movement of said pivotally mounted source of radiant energy, electrically energized means responsive to said receiving means for contacting said legends of conducting material .connection for connecting said signaling means to said legends of conducting material and to said electrically energized means for modulating said electric signaling means in accordance with the angle identifying legend identifying the :angle at which said pivotally mounted source of radiant energy is disposed when said receiving means is energized. z v

19. Signaling apparatus, comprising: means for oscillating a beam of radiant energy through a predetermined angle with respect to a reference line across surfaces of an object normally 7 the aforesaid signals. 1 23. Signaling apparatus, comprising: a source I of radiant energy pivotally mounted to project a beam of radiant energy in search of objects adapted to reflect at least some of the radiant energy, receiving means responsive to radiant energy reflected from any such objects, a member carrying a plurality of angle identifying legends, means for moving said member in accordance with the movement of' said pivotally mounted source of radiant energy, electrically energized means responsive to said receiving means including electric switch means-for producing signals corresponding to the angle identifying legend characterizing the angle at which said pivotally mounted sourceof radiant energy is' disposed when said receiving means is energized, electric signaling means, and connections between said electric switch means and said electric signaling means for modulating said electric signaling means in accordance with the aforesaid signals.

24. Signaling apparatus, comprising: means for producing and projecting a plurality of beams of radiant energy to a 'remote point, at least one of said beam projecting means being pivotally mounted for oscillation through a predetermined angle so that said beams may-be made to converge on surfaces of an object normally adapted to reflect large percentages of such radiant energy, radiant energy sensitive receiving means positioned to be energized by the radiant energy reflected from said object when the beams converge on said object, and means responsive to said receiving means for producing difierent signals for different distances between said radiant energy reflecting object and .said receiving means.

'25. Signaling apparatus, comprising: means for producing and projecting a plurality of beams of radiant energy to a remote point, said V beam projecting means being pivotally mounted for oscillation through a predetermined angle so that said beams may be made to converge on surfaces of an object normally adapted to reflect large percentagesof such radiant energy, radiant' energy sensitive receiving means positioned from said object whenthe beams converge on said object, and means responsive to said receiving means for producing different signals for difierent distances between said radiant energy reflecting obj'ect and said receiving means.

JOHN P. BUCKLEY.

to be energized by the radiant energy reflected 

